The present invention relates to automated assay apparatus used to rapidly detect, for example, proteins, in the diagnosis of infection or diseases. Currently available automated assay apparatus are overly complicated and use a number of pumps and dispensers to deliver different liquid reagents to the reaction chambers.
U.S. Pat. No. 4,859,419 discloses an apparatus for immunoassay of multiple samples of biological fluids. The apparatus contains valved ports and a pump that delivers through a single conduit the same biological fluids to a plural of test vessels. The test vessels are closely connected to each other and share a single port to receive and discharge all biological fluids. Conventional assay apparatus of this type do not allow different liquid reagents to be applied to different test samples using different protocols for different test samples. Further, delivery of multiple liquid reagents through the same conduit lead to potential contamination between different liquid reagents that is not acceptable for most types of tests.
U.S. Pat. No. 5,567,595 discloses an automated blot assay apparatus. This apparatus comprises a rocking tray to assure a mixture of the reaction components and for draining simultaneously of all reaction chambers of a tray to remove solution. Thus requires using only one predetermined schedule for all reaction means. Each solution has its own pump and movable dispenser that makes the programming means and construction complex and requires special features to avoid cross-contamination of solutions. Also, for some assay procedure for better mixture of reagents and cover the test samples is preferable to use horizontal agitation of trays which is not possible by applying the method of draining reaction chambers by inclining the tray.
Valves are widely used for control the fluids flow through individually controlled passageways. For example solenoid controlled valves. To use them with different reagents and a numbers of reaction chambers requires dozens of individual valves results in complexity of control and programming means, to produce the apparatus and use them.
Pinch valves and flexible conduits also used in a wide range of apparatus. Some of the known prior art are designed either normally closed or normally open, the control function, accordingly, is to release or to close the passageway. In some applications, most critical for the valves function is the requirement that the passageway through the conduits should be completely open or close.
Other obstacles to use either type of valves is, that in some cases, due the physical properties of elastomeric conduits, different properties of fluids, and contamination, cause the passageway to close, partially or completely, restricting the flow. Also, with pinch valves, when necessary random activation of two or three sets of multiple pinch valves, there should be used multiple activators. This made the control system more complex and requires more space to place them in apparatus. The known prior art includes elastomeric flow conduits and different shapes of plungers or pistons. These require precise machining operations and quite expensive to produce. Some of the known multiple of pinch valves assemble having the multiple flexible flow conduits wherein the activating the pinch action of one of them impede the pinch state of their neighboring conduits and require special features to avoid this. In some of known multiple conduits pinch valves conduits are placed around or near the actuator, the length of the conduits directed to different sites is different and in some cases due the conduits length and liquid properties the valuable liquid will be waste.